In the early days on Anthrax, Bello used an ESP Precision-styled bass, possibly a 400 series, that had EMG P-bass and J-bass pickups. ESP released this bass as a signature model, available only in Japan, in the mid-to-late 1980s.

During the late 1980s, he switched to an ESP Surveyor P-bass, which had nearly all the same specifications of his previous basses, but with a finished headstock.

Frank began using Fender basses during the beginning of the 1990s